-<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<!--
****************************************************************************
- * Copyright (c) 1998-2009,2010 Free Software Foundation, Inc. *
+ * Copyright (c) 1998-2010,2015 Free Software Foundation, Inc. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* copy of this software and associated documentation files (the *
* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************
- * @Id: curs_color.3x,v 1.35 2010/12/20 00:50:58 tom Exp @
+ * @Id: curs_color.3x,v 1.39 2015/06/06 23:29:02 tom Exp @
-->
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML>
<HEAD>
+<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
+<meta name="generator" content="Manpage converted by man2html - see http://invisible-island.net/scripts/readme.html#others_scripts">
<TITLE>curs_color 3x</TITLE>
<link rev=made href="mailto:bug-ncurses@gnu.org">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</HEAD>
<BODY>
-<H1>curs_color 3x</H1>
-<HR>
+<H1 class="no-header">curs_color 3x</H1>
<PRE>
-<!-- Manpage converted by man2html 3.0.1 -->
<STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG> <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
</PRE>
+<H2>
<a name="h2-NAME">NAME</a></H2><PRE>
<STRONG>start_color</STRONG>, <STRONG>init_pair</STRONG>, <STRONG>init_color</STRONG>, <STRONG>has_colors</STRONG>,
<STRONG>can_change_color</STRONG>, <STRONG>color_content</STRONG>, <STRONG>pair_content</STRONG>, <STRONG>COLOR_PAIR</STRONG>
- <STRONG>curses</STRONG> color manipulation routines
</PRE>
+<H2>
<a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#</STRONG> <STRONG>include</STRONG> <STRONG><curses.h></STRONG>
<STRONG>int</STRONG> <STRONG>start_color(void);</STRONG>
</PRE>
-<H2>DESCRIPTION</H2><PRE>
- <STRONG>Overview</STRONG>
- <STRONG>curses</STRONG> support color attributes on terminals with that ca-
- pability. To use these routines <STRONG>start_color</STRONG> must be
+<H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+
+</PRE>
+<H3><a name="h3-Overview">Overview</a></H3><PRE>
+ <STRONG>curses</STRONG> supports color attributes on terminals with that
+ capability. To use these routines <STRONG>start_color</STRONG> must be
called, usually right after <STRONG>initscr</STRONG>. Colors are always
used in pairs (referred to as color-pairs). A color-pair
consists of a foreground color (for characters) and a
The routine <STRONG>pair_content</STRONG> allows a programmer to find out
how a given color-pair is currently defined.
- <STRONG>Routine</STRONG> <STRONG>Descriptions</STRONG>
+
+</PRE>
+<H3><a name="h3-Color-Rendering">Color Rendering</a></H3><PRE>
+ The <STRONG>curses</STRONG> library combines these inputs to produce the
+ actual foreground and background colors shown on the
+ screen:
+
+ <STRONG>o</STRONG> per-character video attributes (e.g., via <STRONG>waddch</STRONG>),
+
+ <STRONG>o</STRONG> the window attribute (e.g., by <STRONG>wattrset</STRONG>), and
+
+ <STRONG>o</STRONG> the background character (e.g., <STRONG>wbkgdset</STRONG>).
+
+ Per-character and window attributes are usually set by a
+ parameter containing video attributes including a <STRONG>COL-</STRONG>
+ <STRONG>OR_PAIR</STRONG> value. Some functions such as <STRONG>wattr_set</STRONG> use a
+ separate parameter which is the color pair number.
+
+ The background character is a special case: it includes a
+ character value, just as if it were passed to <STRONG>waddch</STRONG>.
+
+ The <STRONG>curses</STRONG> library does the actual work of combining these
+ color pairs in an internal function called from <STRONG>waddch</STRONG>:
+
+ <STRONG>o</STRONG> If the parameter passed to <STRONG>waddch</STRONG> is <EM>blank</EM>, and it us-
+ es the special color pair 0,
+
+ <STRONG>o</STRONG> <STRONG>curses</STRONG> next checks the window attribute.
+
+ <STRONG>o</STRONG> If the window attribute does not use color pair 0,
+ <STRONG>curses</STRONG> uses the color pair from the window at-
+ tribute.
+
+ <STRONG>o</STRONG> Otherwise, <STRONG>curses</STRONG> uses the background character.
+
+ <STRONG>o</STRONG> If the parameter passed to <STRONG>waddch</STRONG> is <EM>not</EM> <EM>blank</EM>, or it
+ does not use the special color pair 0, <STRONG>curses</STRONG> prefers
+ the color pair from the parameter, if it is nonzero.
+ Otherwise, it tries the window attribute next, and fi-
+ nally the background character.
+
+ Some <STRONG>curses</STRONG> functions such as <STRONG>wprintw</STRONG> call <STRONG>waddch</STRONG>. Those
+ do not combine its parameter with a color pair. Conse-
+ quently those calls use only the window attribute or the
+ background character.
+
+
+</PRE>
+<H3><a name="h3-Routine-Descriptions">Routine Descriptions</a></H3><PRE>
The <STRONG>start_color</STRONG> routine requires no arguments. It must be
- called if the programmer wants to use colors, and before
- any other color manipulation routine is called. It is
- good practice to call this routine right after <STRONG>initscr</STRONG>.
- <STRONG>start_color</STRONG> initializes eight basic colors (black, red,
- green, yellow, blue, magenta, cyan, and white), and two
- global variables, <STRONG>COLORS</STRONG> and <STRONG>COLOR_PAIRS</STRONG> (respectively
- defining the maximum number of colors and color-pairs the
- terminal can support). It also restores the colors on the
- terminal to the values they had when the terminal was just
- turned on.
-
- The <STRONG>init_pair</STRONG> routine changes the definition of a color-
- pair. It takes three arguments: the number of the color-
- pair to be changed, the foreground color number, and the
+ called if the programmer wants to use colors, and before
+ any other color manipulation routine is called. It is
+ good practice to call this routine right after <STRONG>initscr</STRONG>.
+ <STRONG>start_color</STRONG> does this:
+
+ <STRONG>o</STRONG> It initializes two global variables, <STRONG>COLORS</STRONG> and <STRONG>COL-</STRONG>
+ <STRONG>OR_PAIRS</STRONG> (respectively defining the maximum number of
+ colors and color-pairs the terminal can support).
+
+ <STRONG>o</STRONG> It initializes the special color pair <STRONG>0</STRONG> to the default
+ foreground and background colors. No other color
+ pairs are initialized.
+
+ <STRONG>o</STRONG> It restores the colors on the terminal to the values
+ they had when the terminal was just turned on.
+
+ <STRONG>o</STRONG> If the terminal supports the <STRONG>initc</STRONG> (<STRONG>initialize_color</STRONG>)
+ capability, <STRONG>start_color</STRONG> initializes its internal table
+ representing the red, green and blue components of the
+ color palette.
+
+ The components depend on whether the terminal uses CGA
+ (aka "ANSI") or HLS (i.e., the <STRONG>hls</STRONG> (<STRONG>hue_lightness_sat-</STRONG>
+ <STRONG>uration</STRONG>) capability is set). The table is initialized
+ first for eight basic colors (black, red, green, yel-
+ low, blue, magenta, cyan, and white), and after that
+ (if the terminal supports more than eight colors) the
+ components are initialized to <STRONG>1000</STRONG>.
+
+ <STRONG>start_color</STRONG> does not attempt to set the terminal's
+ color palette to match its built-in table. An appli-
+ cation may use <STRONG>init_color</STRONG> to alter the internal table
+ along with the terminal's color.
+
+ These limits apply to color values and color pairs. Val-
+ ues outside these limits are not legal, and may result in
+ a runtime error:
+
+ <STRONG>o</STRONG> <STRONG>COLORS</STRONG> corresponds to the terminal database's <STRONG>max_col-</STRONG>
+ <STRONG>ors</STRONG> capability, which is typically a signed 16-bit in-
+ teger (see <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>).
+
+ <STRONG>o</STRONG> color values are expected to be in the range <STRONG>0</STRONG> to <STRONG>COL-</STRONG>
+ <STRONG>ORS-1</STRONG>, inclusive (including <STRONG>0</STRONG> and <STRONG>COLORS-1</STRONG>).
+
+ <STRONG>o</STRONG> a special color value <STRONG>-1</STRONG> is used in certain extended
+ functions to denote the <EM>default</EM> <EM>color</EM> (see <STRONG>use_de-</STRONG>
+ <STRONG>fault_colors</STRONG>).
+
+ <STRONG>o</STRONG> <STRONG>COLOR_PAIRS</STRONG> corresponds to the terminal database's
+ <STRONG>max_pairs</STRONG> capability, which is typically a signed
+ 16-bit integer (see <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>).
+
+ <STRONG>o</STRONG> legal color pair values are in the range <STRONG>1</STRONG> to <STRONG>COL-</STRONG>
+ <STRONG>OR_PAIRS-1</STRONG>, inclusive.
+
+ <STRONG>o</STRONG> color pair <STRONG>0</STRONG> is special; it denotes "no color".
+
+ Color pair <STRONG>0</STRONG> is assumed to be white on black, but is
+ actually whatever the terminal implements before color
+ is initialized. It cannot be modified by the applica-
+ tion.
+
+ The <STRONG>init_pair</STRONG> routine changes the definition of a color-
+ pair. It takes three arguments: the number of the color-
+ pair to be changed, the foreground color number, and the
background color number. For portable applications:
- <STRONG>o</STRONG> The value of the first argument must be between <STRONG>1</STRONG> and
- <STRONG>COLOR_PAIRS-1</STRONG>, except that if default colors are used
- (see <STRONG>use_default_colors</STRONG>) the upper limit is adjusted
- to allow for extra pairs which use a default color in
- foreground and/or background.
+ <STRONG>o</STRONG> The first argument must be a legal color pair value.
+ If default colors are used (see <STRONG>use_default_colors</STRONG>)
+ the upper limit is adjusted to allow for extra pairs
+ which use a default color in foreground and/or back-
+ ground.
- <STRONG>o</STRONG> The value of the second and third arguments must be
- between 0 and <STRONG>COLORS</STRONG>. Color pair 0 is assumed to be
- white on black, but is actually whatever the terminal
- implements before color is initialized. It cannot be
- modified by the application.
+ <STRONG>o</STRONG> The second and third arguments must be legal color
+ values.
If the color-pair was previously initialized, the screen
is refreshed and all occurrences of that color-pair are
changed to the new definition.
- As an extension, ncurses allows you to set color pair 0
+ As an extension, ncurses allows you to set color pair <STRONG>0</STRONG>
via the <STRONG>assume_default_colors</STRONG> routine, or to specify the
use of default colors (color number <STRONG>-1</STRONG>) if you first in-
voke the <STRONG>use_default_colors</STRONG> routine.
The <STRONG>init_color</STRONG> routine changes the definition of a color.
It takes four arguments: the number of the color to be
changed followed by three RGB values (for the amounts of
- red, green, and blue components). The value of the first
- argument must be between <STRONG>0</STRONG> and <STRONG>COLORS</STRONG>. (See the section
- <STRONG>Colors</STRONG> for the default color index.) Each of the last
- three arguments must be a value between 0 and 1000. When
- <STRONG>init_color</STRONG> is used, all occurrences of that color on the
- screen immediately change to the new definition.
-
- The <STRONG>has_colors</STRONG> routine requires no arguments. It returns
- <STRONG>TRUE</STRONG> if the terminal can manipulate colors; otherwise, it
+ red, green, and blue components). The first argument must
+ be a legal color value; default colors are not allowed
+ here. (See the section <STRONG>Colors</STRONG> for the default color in-
+ dex.) Each of the last three arguments must be a value in
+ the range <STRONG>0</STRONG> through <STRONG>1000</STRONG>. When <STRONG>init_color</STRONG> is used, all
+ occurrences of that color on the screen immediately change
+ to the new definition.
+
+ The <STRONG>has_colors</STRONG> routine requires no arguments. It returns
+ <STRONG>TRUE</STRONG> if the terminal can manipulate colors; otherwise, it
returns <STRONG>FALSE</STRONG>. This routine facilitates writing terminal-
- independent programs. For example, a programmer can use
- it to decide whether to use color or some other video at-
+ independent programs. For example, a programmer can use
+ it to decide whether to use color or some other video at-
tribute.
- The <STRONG>can_change_color</STRONG> routine requires no arguments. It
- returns <STRONG>TRUE</STRONG> if the terminal supports colors and can
- change their definitions; other, it returns <STRONG>FALSE</STRONG>. This
+ The <STRONG>can_change_color</STRONG> routine requires no arguments. It
+ returns <STRONG>TRUE</STRONG> if the terminal supports colors and can
+ change their definitions; other, it returns <STRONG>FALSE</STRONG>. This
routine facilitates writing terminal-independent programs.
- The <STRONG>color_content</STRONG> routine gives programmers a way to find
+ The <STRONG>color_content</STRONG> routine gives programmers a way to find
the intensity of the red, green, and blue (RGB) components
in a color. It requires four arguments: the color number,
- and three addresses of <STRONG>short</STRONG>s for storing the information
- about the amounts of red, green, and blue components in
- the given color. The value of the first argument must be
- between 0 and <STRONG>COLORS</STRONG>. The values that are stored at the
- addresses pointed to by the last three arguments are be-
- tween 0 (no component) and 1000 (maximum amount of compo-
- nent).
-
- The <STRONG>pair_content</STRONG> routine allows programmers to find out
- what colors a given color-pair consists of. It requires
- three arguments: the color-pair number, and two addresses
- of <STRONG>short</STRONG>s for storing the foreground and the background
- color numbers. The value of the first argument must be
- between 1 and <STRONG>COLOR_PAIRS-1</STRONG>. The values that are stored
- at the addresses pointed to by the second and third argu-
- ments are between 0 and <STRONG>COLORS</STRONG>.
-
- <STRONG>Colors</STRONG>
+ and three addresses of <STRONG>short</STRONG>s for storing the information
+ about the amounts of red, green, and blue components in
+ the given color. The first argument must be a legal color
+ value, i.e., <STRONG>0</STRONG> through <STRONG>COLORS-1</STRONG>, inclusive. The values
+ that are stored at the addresses pointed to by the last
+ three arguments are in the range <STRONG>0</STRONG> (no component) through
+ <STRONG>1000</STRONG> (maximum amount of component), inclusive.
+
+ The <STRONG>pair_content</STRONG> routine allows programmers to find out
+ what colors a given color-pair consists of. It requires
+ three arguments: the color-pair number, and two addresses
+ of <STRONG>short</STRONG>s for storing the foreground and the background
+ color numbers. The first argument must be a legal color
+ value, i.e., in the range <STRONG>1</STRONG> through <STRONG>COLOR_PAIRS-1</STRONG>, inclu-
+ sive. The values that are stored at the addresses pointed
+ to by the second and third arguments are in the range <STRONG>0</STRONG>
+ through <STRONG>COLORS</STRONG>, inclusive.
+
+
+</PRE>
+<H3><a name="h3-Colors">Colors</a></H3><PRE>
In <STRONG><curses.h></STRONG> the following macros are defined. These are
- the default colors. <STRONG>curses</STRONG> also assumes that <STRONG>COLOR_BLACK</STRONG>
- is the default background color for all terminals.
+ the standard colors (ISO-6429). <STRONG>curses</STRONG> also assumes that
+ <STRONG>COLOR_BLACK</STRONG> is the default background color for all termi-
+ nals.
<STRONG>COLOR_BLACK</STRONG>
<STRONG>COLOR_RED</STRONG>
</PRE>
-<H2>
RETURN VALUE</H2><PRE>
- The routines <STRONG>can_change_color()</STRONG> and <STRONG>has_colors()</STRONG> return
+<H2>
<a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
+ The routines <STRONG>can_change_color()</STRONG> and <STRONG>has_colors()</STRONG> return
<STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>.
All other routines return the integer <STRONG>ERR</STRONG> upon failure and
- an <STRONG>OK</STRONG> (SVr4 specifies only "an integer value other than
+ an <STRONG>OK</STRONG> (SVr4 specifies only "an integer value other than
<STRONG>ERR</STRONG>") upon successful completion.
- X/Open defines no error conditions. This implementation
- will return <STRONG>ERR</STRONG> on attempts to use color values outside
- the range 0 to COLORS-1 (except for the default colors ex-
- tension), or use color pairs outside the range 0 to COL-
- OR_PAIRS-1. Color values used in <STRONG>init_color</STRONG> must be in
- the range 0 to 1000. An error is returned from all func-
- tions if the terminal has not been initialized. An error
- is returned from secondary functions such as <STRONG>init_pair</STRONG> if
+ X/Open defines no error conditions. This implementation
+ will return <STRONG>ERR</STRONG> on attempts to use color values outside
+ the range <STRONG>0</STRONG> to COLORS-1 (except for the default colors ex-
+ tension), or use color pairs outside the range <STRONG>0</STRONG> to <STRONG>COL-</STRONG>
+ <STRONG>OR_PAIRS-1</STRONG>. Color values used in <STRONG>init_color</STRONG> must be in
+ the range <STRONG>0</STRONG> to <STRONG>1000</STRONG>. An error is returned from all func-
+ tions if the terminal has not been initialized. An error
+ is returned from secondary functions such as <STRONG>init_pair</STRONG> if
<STRONG>start_color</STRONG> was not called.
<STRONG>init_color</STRONG>
- returns an error if the terminal does not support
- this feature, e.g., if the <EM>initialize</EM><STRONG>_</STRONG><EM>color</EM> capa-
+ returns an error if the terminal does not support
+ this feature, e.g., if the <EM>initialize</EM><STRONG>_</STRONG><EM>color</EM> capa-
bility is absent from the terminal description.
<STRONG>start_color</STRONG>
- returns an error if the color table cannot be al-
+ returns an error if the color table cannot be al-
located.
</PRE>
- In the <EM>ncurses</EM> implementation, there is a separate color
+<H2>
<a name="h2-NOTES">NOTES</a></H2><PRE>
+ In the <EM>ncurses</EM> implementation, there is a separate color
activation flag, color palette, color pairs table, and as-
- sociated COLORS and COLOR_PAIRS counts for each screen;
- the <STRONG>start_color</STRONG> function only affects the current screen.
+ sociated COLORS and COLOR_PAIRS counts for each screen;
+ the <STRONG>start_color</STRONG> function only affects the current screen.
The SVr4/XSI interface is not really designed with this in
- mind, and historical implementations may use a single
+ mind, and historical implementations may use a single
shared color palette.
Note that setting an implicit background color via a color
- pair affects only character cells that a character write
- operation explicitly touches. To change the background
- color used when parts of a window are blanked by erasing
+ pair affects only character cells that a character write
+ operation explicitly touches. To change the background
+ color used when parts of a window are blanked by erasing
or scrolling operations, see <STRONG><A HREF="curs_bkgd.3x.html">curs_bkgd(3x)</A></STRONG>.
- Several caveats apply on 386 and 486 machines with VGA-
+ Several caveats apply on 386 and 486 machines with VGA-
compatible graphics:
- <STRONG>o</STRONG> COLOR_YELLOW is actually brown. To get yellow, use
+ <STRONG>o</STRONG> COLOR_YELLOW is actually brown. To get yellow, use
COLOR_YELLOW combined with the <STRONG>A_BOLD</STRONG> attribute.
<STRONG>o</STRONG> The A_BLINK attribute should in theory cause the back-
- ground to go bright. This often fails to work, and
+ ground to go bright. This often fails to work, and
even some cards for which it mostly works (such as the
- Paradise and compatibles) do the wrong thing when you
- try to set a bright "yellow" background (you get a
+ Paradise and compatibles) do the wrong thing when you
+ try to set a bright "yellow" background (you get a
blinking yellow foreground instead).
<STRONG>o</STRONG> Color RGB values are not settable.
</PRE>
-<H2>
PORTABILITY</H2><PRE>
- This implementation satisfies XSI Curses's minimum maxi-
+<H2>
<a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
+ This implementation satisfies XSI Curses's minimum maxi-
mums for <STRONG>COLORS</STRONG> and <STRONG>COLOR_PAIRS</STRONG>.
- The <STRONG>init_pair</STRONG> routine accepts negative values of fore-
- ground and background color to support the <STRONG>use_de-</STRONG>
- <STRONG>fault_colors</STRONG> extension, but only if that routine has been
+ The <STRONG>init_pair</STRONG> routine accepts negative values of fore-
+ ground and background color to support the <STRONG>use_de-</STRONG>
+ <STRONG>fault_colors</STRONG> extension, but only if that routine has been
first invoked.
- The assumption that <STRONG>COLOR_BLACK</STRONG> is the default background
- color for all terminals can be modified using the <STRONG>as-</STRONG>
+ The assumption that <STRONG>COLOR_BLACK</STRONG> is the default background
+ color for all terminals can be modified using the <STRONG>as-</STRONG>
<STRONG>sume_default_colors</STRONG> extension.
- This implementation checks the pointers, e.g., for the
- values returned by <STRONG>color_content</STRONG> and <STRONG>pair_content</STRONG>, and
+ This implementation checks the pointers, e.g., for the
+ values returned by <STRONG>color_content</STRONG> and <STRONG>pair_content</STRONG>, and
will treat those as optional parameters when null.
</PRE>
+<H2>
<a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
<STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>, <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, <STRONG>curs_vari-</STRONG>
<STRONG><A HREF="curs_variables.3x.html">ables(3x)</A></STRONG>, <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>
<STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
</PRE>
-<HR>
-<ADDRESS>
-Man(1) output converted with
-<a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a>
-</ADDRESS>
+<div class="nav">
+<ul>
+<li><a href="#h2-NAME">NAME</a></li>
+<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
+<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
+<ul>
+<li><a href="#h3-Overview">Overview</a></li>
+<li><a href="#h3-Color-Rendering">Color Rendering</a></li>
+<li><a href="#h3-Routine-Descriptions">Routine Descriptions</a></li>
+<li><a href="#h3-Colors">Colors</a></li>
+</ul>
+</li>
+<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
+<li><a href="#h2-NOTES">NOTES</a></li>
+<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
+<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
+</ul>
+</div>
</BODY>
</HTML>
projects / ncurses.git / blobdiff